/Engine/Plugins/Animation/ControlRig/Source/ControlRig/Public/Rigs/RigHierarchy.h
typedef TMulticastDelegate_ThreeParams< void, [ERigHierarchyNotification](API\Plugins\ControlRig\Rigs\ERigHierarchyNotification), [URigHierarchy](API\Plugins\ControlRig\Rigs\URigHierarchy) *, const [FRigBaseElement](API\Plugins\ControlRig\Rigs\FRigBaseElement) * > FRigHierarchyModifiedEvent